TIDUF71A March   2024  – November 2024

 

  1.   1
  2.   Description
  3.   Resources
  4.   Features
  5.   Applications
  6.   6
  7. 1System Description
  8. 2System Overview
    1. 2.1 Block Diagram
    2. 2.2 Design Considerations
    3. 2.3 Highlighted Products
      1. 2.3.1 AFE7950-SP
      2. 2.3.2 LMK04832-SEP
      3. 2.3.3 LMX2694-SEP
      4. 2.3.4 TRF0208-SEP
      5. 2.3.5 TPS7H4010-SEP
      6. 2.3.6 TPS73801-SEP
  9. 3Hardware, Software, Testing Requirements, and Test Results
    1. 3.1 Hardware Requirements
    2. 3.2 Software Requirements
    3. 3.3 Test Setup
    4. 3.4 Hardware Configuration
    5. 3.5 Test Procedure
      1. 3.5.1 Initial TSW14J56 Setup
      2. 3.5.2 Reference Design Test Procedure
    6. 3.6 Test Results
      1. 3.6.1 TXA/B DAC Output Test Results
      2. 3.6.2 TXC/D DAC Output Test Results
      3. 3.6.3 RXA/B ADC Test Results
      4. 3.6.4 RXC/D ADC Test Results
      5. 3.6.5 FB2 ADC Test Results
    7. 3.7 Alternative Configurations
      1. 3.7.1 Internal AFE7950-SP PLL/VCO
        1. 3.7.1.1 The Easy Way - Internal PLL/VCO
        2. 3.7.1.2 The Proper Way - Internal PLL/VCO
      2. 3.7.2 Internal TCXO Operation
      3. 3.7.3 400MHz Bandwidth RX Configuration
  10. 4Design and Documentation Support
    1. 4.1 Design Files
      1. 4.1.1 Schematics
      2. 4.1.2 BOM
    2. 4.2 Tools
      1. 4.2.1 Latte Commands
      2. 4.2.2 Config Files
        1. 4.2.2.1 Latte Config Files
        2. 4.2.2.2 LMK / LMX Config Files
      3. 4.2.3 Troubleshooting
    3. 4.3 Hardware Identification Information
      1. 4.3.1 Rework Modifications
      2. 4.3.2 Reference Design Board Location Identification
      3. 4.3.3 FMC Interface Board Location Identification
    4. 4.4 Documentation Support
    5. 4.5 Support Resources
    6. 4.6 Trademarks
  11. 5About the Author
  12. 6Revision History

3.7.1.2 The Proper Way - Internal PLL/VCO

The proper way for using the internal PLL/VCO is to bypass the LMX2694 completely and drive the reference directly from the LMK04832. This approach requires solder modifications on the board (this is not the easy way).

The following hardware changes are needed to implement this configuration:

  • C181, C194: Do Not Install
  • C28, C45: Place 0.1uF coupling caps
  • R48: Do Not Install (disengages power to the LMX2694)

The bring-up sequence modifies programming files per the following:

  • LMK04832-SEP: LMK04832-SEP_TICsPro_491p52_CLKINBypass_LMXBypass.tcs
  • Latte: AFE7950-SP_EVM_Mode2H.py

The LMK file outputs a 491.52MHz reference that feeds directly to the AFE7950-SP clock input. No programming is done on the LMX part.